The Definitions of Persistence of Vision in Film Studies

By
© 2001 Pamela Cole
Georgia State University
Fall 2001

Abstract

Almost without exception, the film studies community has accepted persistence of vision as the miraculous visual “defect” that allows us to view film as motion. There is a small, unobserved circle of skeptics regarding this premise, as published in a few seldom cited, but highly controversial, academic papers. The film community has curiously given little credence to studies that question the reign of persistence of vision in film theory. Even within the film community, the definition of persistence of vision varies wildly to suit whatever explanation is needed. This paper will present a content analysis of six film history texts to see how persistence of vision (or the ability to perceive motion in films) is defined in major film history texts.

Introduction

Over 175 years ago, long before the existence of the field of film studies, a British physician, Peter Mark Roget, observed and documented an optical illusion while looking through the spokes of a wagon wheel.  In the course of time, this illusion came to be known as “persistence of vision.” Roget is credited with “discovering” persistence of vision even though he never used the phrase in his 1824 paper, "Explanation of an optical deception in the appearance of the spokes of a wheel seen through vertical apertures" (cited by Anderson, 1978).  Roget also never attempted to apply this optical illusion to an understanding of perceived motion in film, which is understandable given the absence of any real film activity at the time. Roget later gained fame for his book, Roget’s Thesaurus, a document devoted to synonyms.

Apparently, it was film historian Terry Ramsaye who, a hundred years later in 1926, adopted Roget’s illusion, gave it a slick-sounding, intellectual moniker (persistence of vision), and applied it to an understanding of our ability to perceive motion in film. In a strange irony, given Roget’s real call to fame as the great synonymist, Ramsaye seems to have coined the phrase, “persistence of vision,” as a synonym for the optical illusion Roget observed. He did this by incorrectly citing the title of Roget’s 1824 paper as “Persistence of Vision with Regards to Moving Objects” (Anderson & Fisher, 1978).

Today, the phrase “persistence of vision” is embedded in film jargon, and is included in the naming of many film-related projects. For example: the San Francisco International Film Festival presents the “Persistence of Vision Award” each year; Persistence of Vision Ray Tracer™ is the name of a popular piece of software used to create three-dimensional graphics; numerous books about film include the phrase in the book title, as in “Persistence of Vision: The Films of Robert Altman” by Neil Feineman (1978) or “Persistence of Vision: an impractical guide to Producing a Feature Film for under $30,000” (Gaspard & Newton, 1996). Persistence of Vision  is even the name of the journal published by the film faculty of the City University of New York.

Almost without exception, the film community has accepted persistence of vision as the miraculous visual response that allows us to view film as motion. There is a small, unobserved circle of skeptics regarding this premise, as published in a few seldom cited, but highly controversial, academic papers. The film community has stubbornly resisted any outside thought regarding the notion of persistence of vision in film theory. Even within the film community, the definition of persistence of vision varies to suit whatever explanation is needed.

This paper will look at how persistence of vision is defined in six film history texts published in the last 20 years. This content analysis will illustrate, furthermore, how these definitions serve or disserve the understanding of motion perception in the community of film scholarship.

Literature Review

The literature supporting persistence of vision in film theory is legion, while the literature opposing it is quite sparse. Interestingly, the term “persistence of vision” is no longer used in perceptual psychology where the concept has been rejected and replaced by more viable explanations, such as short-range apparent motion (Anderson & Anderson, 1993).  Nonetheless, the phrase and the theory of persistence of vision flourishes in contemporary film studies literature. To read a definition of persistence of vision and its supposed explanation for our ability to perceive motion in film, one has only to pick up any number of film history or film theory texts of the last 75 years. (The notion has even spread to the television industry, where persistence of vision is also claimed as the way we perceive motion in television [Jowett, 1994].) To find other theories that explain our ability to perceive motion from a series of static images on a strip of film, one has to look a bit harder.

Since the focus of this paper is the commonly accepted definitions of persistence of vision as the way we perceive motion in films, this literature review will focus instead on the articles that are in opposition to this belief. There exists but a handful of arguments. Opponents of persistence of vision often cite Max Wertheimer’s 1912 Gestalt psychology work that resulted in the phi phenomenon and beta movement theory (cited by Nichols & Lederman, 1978).  Recent articles rejecting persistence of vision have been put forth by Joseph and Barbara Anderson[1]. They pronounced that:

“Persistence of Vision” found its way into film literature in two ways: 1) through a lack of careful scholarship among film writers, and 2) because of a considerable amount of confusion about the nature of apparent motion among early investigators of the phenomenon.” (Anderson & Anderson, 1993)

In an earlier paper, these authors put forth the idea of persistence of vision as myth which basically covers up the schism in film theory between aesthetic and psychological studies (Anderson & Fisher, 1978). In his cognitive approach, Anderson believes that perception of motion must be a product of retinal input and psychological interpretation, as a result of evolutional development (Anderson, 1996). He rejects the idea that the eye holds onto an image for a few seconds, and then fuses the image into the next image, thereby blanketing the blank motionless space in between. He cites recent perceptual psychological studies that offer new explanations for the apparent motion we perceive in films. According to Fredericksen (2000), “Before Anderson’s book, there was no systematic ecological approach to film” (p. 97).

Another predominant opposing opinion was presented the same year (1978), and at the same conference where Anderson & Fisher presented their paper. At that time, Nichols & Leder (1978) unequivocally pronounced that “virtually every account of the perception of movement in film texts [is] wrong... the impression of movement is not due to persistence of vision.”

But even Nichols & Lederman and Anderson & Fisher disagree about the probable cause of perception of motion in film. Anderson & Anderson ultimately settle upon “short-range apparent motion” (Anderson, 1993) as a probable explanation, while Nichols & Leder suggest “beta movement” as described by Wertheimer as a possible explanation. Nonetheless, they both dismiss persistence of vision as a plausible explanation.

While much has been written to perpetuate the theory of persistence of vision, there has been no content analysis done on the mainstream definitions of persistence of vision which are being presented to film scholars. This paper will look at six film history texts (published from 1981-2001), which are easily obtained in most university libraries or bookstores, and provide a content analysis of the way that persistence of vision is defined in each text.

A Content analysis of Six Film History Texts

The following six texts were selected for this study:

These texts were selected at random, solely on the basis of their instant accessibility from a university film library.

Sobchak, Thomas & Sobchak, Vivian. (1980).  An Introduction to Film. This is the earliest text in the study. Sobchak & Sobchak  took persistence of vision very seriously. In the first chapter of the book, Space in the Cinema, under the heading of “The Eye and the Camera,” the first sentence reads:

“Strangely enough, motion pictures are only possible because of a flaw in human vision; we are all victims or beneficiaries of persistence of vision.” (Sobchak & Sobchak, 1980, p. 19)

The paragraph then goes on to explain persistence of vision using the example of looking at the sun and then continuing to see the image wherever one looks. This phenomenon is widely known as “after-images” and has no real relation to perception of motion in film, according to both Nichols & Lederman (1978) and Anderson & Fisher (1978). Clearly, Sobchak & Sobchak were either unaware of these articles, or chose to disregard them.

Sobchak & Sobchak (1980, p.19) say that persistence of vision “blends individual instances of movement together and we see what appears to be continuous movement.“ In all, three paragraphs are devoted to the definition of persistence of vision and the way that projectors are designed to make use of this phenomenon. A full page graphic showing pages of a “flip-book” is included to illustrate persistence of vision. The entire definition takes about two-and-a-half pages.

No mention is made of differing opinions about the way we perceive motion in motion pictures. Sobchak & Sobchak present persistence of vision as the definitive answer.

Cook, David A. (1981). A History of Narrative Film. Published the following year, Cook’s text presents quite a different picture of persistence of vision. In the first paragraph of the first page of chapter one, “Origins,” Cook mentions the “optical phenomenon known as persistence of vision…known to the ancient Egyptians but first described scientifically by Peter Mark Roget in 1824” (1981, p. 1). He defines persistence of vision as the way “the brain retains images cast upon the retina of the eye for approximately one-twentieth to one-fifth of a second beyond their actual removal from the field of vision” (Cook, 1981, p. 1).

 We do not know where Cook came upon the information that the ancient Egyptians knew about persistence of vision, since no footnote or reference is offered. He is also incorrect in stating that Roget described the phenomenon. Roget’s paper “described a case in which a series of moving points results in the perception of a static image...In cinema, a series of static images results in the illusion of motion” (Anderson & Fisher, 1978). Cook, however, does include a footnote that cites Anderson & Fisher “The Myth of Persistence of Vision.” Cook asserts that Anderson’s article is “a provocative but unsubstantiated argument that Roget’s conception has been badly misinterpreted by film historians and that, in fact, very little is really known about the cognitive processes involved in the perception of motion” (1981, p. 1).

Gomery, Douglas. (1991). Movie History: A Survey. Ten years later, in 1991, Gomery avoids the whole issue by not mentioning the phrase, “persistence of vision.” This was the only text of the six texts in this study which did not mention “persistence of vision.” Even though Gomery promised to “chart the invention, innovation, and diffusion of the movies in the years before the cinema  became a worldwide phenomena,” adding that “we shall discover how the movies came to be invented” (1991, p. 4), he manages to do so without the theory of persistence of vision. The only explanation Gomery offers for how we observe motion in motion pictures is that “moving images depend on individual still photographs appearing in rapid succession” (1991, p. 4).

Mast, Gerald & Kawin, Bruce. (2000). A Short History of the Movies-7^th Edition. Mast & Kawin present a definition of persistence of vision in chapter two, under the heading of “Persistence of Vision.” Their discussion indicates that in the 21^st century, persistence of vision has once again picked up steam. Mast & Kawin (2000) go to great details to explain the phenomenon of persistence of vision. Basically, they surmise that “the retina blurs the individual points of light into a circular figure” when comparing persistence of vision to what the eye sees when a flashlight is rotated in a circular pattern (p. 8). They summon Max Wertheimer and Hugo Munsterberg in their defense. They claim that “persistence of vision and the phi phenomenon make movie action seem as fluid and uninterrupted as live action.” (Mast & Kawin, 2000, p. 9) (Anderson would say that “not only is the traditional persistence of vision explanation of motion in the motion picture inadequate, but that explanations associated with apparent movement such as Wertheimer’s phi movement are also inadequate and misleading.” [1996, p. 61.])

Interestingly, Mast & Kawin (like Cook) also claim that persistence of vision was “known by the ancients,” whomever they may be (2000, p. 8). (Are they referring to ancient American Indians, ancient Egyptians, or perhaps, ancient Mongolians?) Again, we have no reference to validate that claim of “ancient” knowledge. They go on to ground their definition in a long and detailed explanation of “stroboscopic toys” which they say were invented to demonstrate persistence of vision. 

In all, the “Persistence of Vision” heading and ensuing explanation requires three full pages.

Prince, Stephen. (2001). Movies and Meaning: An Introduction to Film –2^nd edition. Prince tackles the subject head-on in his book, with a special two-page section in chapter two, called “How Movies create the Impression of Motion on Screen.” In this section, Prince (2001) does not attribute the perception of motion in film entirely to persistence of vision. Instead, he says that it is “due to several factors of perception” including persistence of vision, flicker fusion, and beta movement (p. 88). Prince (2001) defines persistence of vision as the phenomenon where “the retina of the eye retains an image for a fraction of a second after the source is gone“ (p. 88).  He also defines persistence of vision as being synonymous with retinal after-images, which is considered to be an entirely different visual phenomenon by Nichols & Leder (1978) and Anderson & Fisher (1978), and is inconsistent with Roget’s original paper. He makes no mention of any controversy surrounding the theory of persistence of vision, but instead, seems to try to combine several theories into one, under the guise of “motion perception is a complex phenomenon” (Prince, 2001, p. 88). He does not, however, deny that persistence of vision is a factor in the perception of motion in film.

Prince offers a more complex, although less clear definition of why we perceive motion in film, and he goes on to apply his theory to television. He uses examples of “closely spaced light bulbs being illuminated in rapid sequence in a darkened room.” (Prince, 2001, p. 89) His final summary strives to simplify his definition by saying that:

“In these ways, the most fundamental features of cinema—the appearance of continuous light and motion –are built on shared characteristics of perception common to all viewers. These features are automatic. Viewers do not have to make any effort to bring them into play. The cinema activates universal perceptual abilities held by all members of its audiences.” (Prince, 2001, p. 89)

Sklar, Robert. (2001). Film: An International History of the Medium – 2^nd edition. This most recent text on international film history is by Robert Sklar. Sklar mentions persistence of vision in chapter one,  “Cinema Society, and Science,”  under the heading of “Motion Toys.” Sklar (2001) broadly claims that “scientists in the 1820s became intrigued with a phenomenon they called persistence of vision” (p. 16). He does not say what scientists, nor is he correct when he says they used the phrase “persistence of vision” in the 1820s. It would be over a hundred years before this phrase was introduced. He mentions Roget’s paper, mainly as the catalyst for the construction of motion toys.

Sklar does cast some doubt on the validity of persistence of vision. He writes  that the term “persistence of vision,” while widely mentioned in film histories, “is no longer accepted in the field of perceptual psychology” (Sklar, 2001, p. 17).  He then mentions the concept of the “after-image” and cites Nichols & Leder’s 1978 paper, “Flicker and Motion in Film” (Sklar, 2001, p. 17).  He does not , however, mention Anderson & Anderson and their rejection of perception of vision. 

Conclusion

A quantitative summary of the findings are listed here. Of the six texts: (see Table 1)

·         Five accept persistence of vision as the primary explanation for how we perceive motion in film.

·         Only one of the texts (Sobchak & Sobchak, 1980), the earliest text, describes persistence of vision as the only acceptable explanation for perception of motion in film.

·         Two of the texts mention some opposition to persistence of vision as the explanation for how we perceive motion in film.

·         Two of the texts combine persistence of vision with other theories as an explanation.

·         One of the texts (Gomery, 1991), does not offer any definition of persistence of vision. Curiously, this is the text in the midpoint of the timeline studied.

Motion Toys. Of the five texts that define persistence of vision, four rely on the description of “stroboscopic” or motion toys in their definition. Sobchak & Sobchak (1980, p. 3-4) even claim that these toys are the “ancestors of our animated films” and that “these parlor toys were the first steps towards the motion picture.” Most of the texts claim that the toys were devised in response to Roget’s 1824 paper, or to Joseph Antoine Ferdinand Plateau’s 1829 research. According to the texts, the invention of motion toys was an attempt to demonstrate the results of the work of both Roget and Plateau, and to demonstrate the existence of persistence of vision.  Cook says that “persistence of vision was exploited for the purpose of optical entertainment for many years before the invention of photography” through these toys (Cook, 1981, p. 2).

It does appear that the introduction of these toys into society in the 19^th century, and their popularity at a time when there were few available entertainment devices, may have had a profound impact on the acceptance of persistence of vision as an explanation. These devices are still used today by educators, to explain the concept of persistence of vision to children. The delightful demonstration of a simple motion toy satisfies most people’s curiosity about how we perceive motion in film. These popular education tools serve to further entrench the belief in persistence of vision.

What is the correct definition? Not unlike the Bible, Roget’s original manuscript was interpreted and misinterpreted to serve a specific purpose and bridge a specific gap in our understanding. In search of a simple answer to the grand mystery of how we perceive motion in projected film, early film theorists and filmmakers happily accepted the concept of persistence of vision as the obvious answer. It appears that modern film theorists and historians are also happy with this explanation, be it right or wrong. [1]

Director Martin Scorsese credits his introduction to persistence of vision as a child as the inspiration that made him want to make movies. He describes watching the main character in the film The Magic Box (1951) flip through the pages of a book and describe the ensuing illusion of motion as “persistence of vision.” Scorsese says, “This was miraculous to me as a child. I went home and tried it myself with telephone books. I was transfixed. I wanted to make movies” (Scorsese, 1998). Scorsese, equipped with this common definition of persistence of vision, became one of Hollywood’s leading film directors. It appears this definition did not hamper his understanding of film or film making.

Perhaps it isn’t the definition that matters so much, since film writers over the last 100 years have at times been quite creative in defining persistence of vision. Perhaps it is only the vision inspired by the definition that is important. The workings of the human visual system are enormously complicated. Fully understanding what is known about it, is beyond the ability of most people. It appears, therefore, that film scholars have embraced the more simplistic explanation of persistence of vision which appears in most texts, as the explanation for why we perceive motion in film. Most of us are able to grasp its implications, and some of us are inspired to produce its potential. Would a better understanding of a more accurate explanation for our ability to perceive motion in film produce better film history, criticism, and theory (not to mention, better films)? Film scholars (historians, critics, and theorists) in the 21^st century should at least be intrigued by this question.

NOTES:

1. To include a bit of feminist theory perhaps, let us take a closer look at the preface to Anderson’s book for another possible explanation of the persistence of persistence of vision. Here he feels compelled to include a paragraph which defends his use of the masculine pronouns, “he” and “his” rather than “she” or “her.” Anderson claims that “the repeated use of he or she or his or her was intrusive and distracted from the explanation“ (Anderson, 1996, p. xi). This sounds distinctly like the claims of some film writers who defend the use of the term “persistence of vision” because it is “’simple to understand,’ ‘elegant’ even ‘poetic’,” (Herbert, 2001) and thus would certainly not distract from the explanation of how we perceive motion in film, as perhaps would the more complex explanation offered by Anderson of “short-range apparent motion.”  

Anderson goes on to say that “there has been a long tradition in the English language for use of the masculine pronoun as gender inclusive” (Anderson, 1996, p. xi). The contemporary film historian could also argue that there has been a long tradition of the acceptance of persistence of vision in film studies, therefore, why change tradition to be inclusive of other ideas? Apparently, this is the argument of most film scholars.